Method of and apparatus for producing photographic prints.



Patented Feb. 29, 1916.

J. E. THORNTON.

APPLICATION FILED JUNE 21, 1911.

METHOD OF AND APPARATUS FOR PRODUCING PHOTOGRAPHIC PRINTS.

Evan/5f Jiilzzdward Ham/a2 UNITED STATES PATENT OFFICE.

some nnwann 'rnoanron; or noonnsrnn,'nnw YORK, assreuoa 'ro JOHN ownnn ,OBRIEN, or'nancnnsrnn, ENGLAND.

- METHOD OFAND APPARATUS FOR PRODUCING PHOTOGRAPHIC PRINTS.

' Specification of Letters Patent.

Patented Feb. 29, 1916.

Application filed June 21, 1911. Serial No. 634,573.

To all whom it may concern: Be it known that I, JOHN EDWARD THOR N- TON, a subject of the King of Great Britam,

and resident of Rochester, in the county of Monroe and State of New-York, have invented certain newand useful Improvements in Methods of and Apparatus for Producing Photographic Prints, of which the following is a specification.

This invention relates tothe manufacture of a photographic strip of film-tape provided with a succession of views or images.

It is particularly applicable to the manufacture of films for use in motion-projection, though it is also applicable wherever a large number of views or images must be printed and developed.

The object of the invention is to provide a method, and apparatus for carrying this method into practice, whereby printed stri s of considerable or indefinite length may produced by a continuous operation, so that the blank material may 'be introduced cona zigzag or tortuous path as has been pre viously proposed in connection with more or less analo ous operations, I conduct the strip over suitable drums or rollers in such a manner that it follows a path which may be described as substantially helicalin form. This is accomplished, in the simplest manner, by coiling the strip repeatedly and helically around two substantially-parallel chamber rollers, and the extent of departure of the path from a true helix depends upon the distance ,between the rollers. In any case a valuable characteristic of the arrangement resides in the fact that in a comparatively limited space a great length of the strip may be coiled and at the same time fully exposed, while the strip may also pass continuously, at any required speed, through this path when the rollers are caused or permitted to rotate by the application of power.

As compared with a zigzag path the present arrangement has several pronounced advantages. In the first place, it causes the portions of the material in successive turns to lie all in the same plane and with the sensitized surfaces facing in the same direction, which is of particular utility in the printing operation, as it permits the use of actinic light falling upon the successive turns from the same direction, thus simplifying the arrangement of the sources of light and economizing in the expenditure of energy. In the second place the novel arrangement permits the use of very simple mechanism for supporting and moving the strip, since two rollers, sufliciently elongated, may be used to support any required length of material. A third advantage of the present arrangement resides in the fact that the material is not bent alternately in opposite cording as it is desired to produce positive or negative prints, and this film is moved constantly'at the same speed as the sensitized strip to be printed, so that the two strips travel in contact through a certain space in which they are exposed to actiniclight and the endless negative or positive film is thus used over and over to print successive portions of the sensitized strip.

Other objects and features of the invention will be set forth in connection with the following description of the apparatus illustrated in the accompanying drawings.

In the drawings, which are diagrammatic in character, Figure 1 is a sectional side elevation of a printing apparatus constructed in accordance with the present invention. Fig. 2 is a section on the line 33 in Fig. 1.

The invention is applicable to the production of finished photographic material of various kinds in strip form, but as it is-particularly applicable .to the production of films for use in projecting-lanterns I have illustrated an apparatus designed particularly for this purpose, and inthe following description the material to be acted upon will, for convenience, be designated hereinafter as the filmfwhile the endless film through which the sensitized film is printed will be hereinafter designated as the negative, although obviously a positivefilm may be used for this latter purpose 'where it is desired to produce negative prints.

The characteristic arrangement of parts by which the film is conducted in a helical path is preferably employed in the illustrated apparatus. The two rollers about which the film passes may be arranged in either vertical or horizontal relation, but they are most conveniently and compactly arranged in vertical relation, one roller 1 being journaled near the ceiling of the room or compartment 2, and the other roller 3 being'journaled near the floor.

' The film 4: is shown as comparatively wide for convenience in illustration, but in actual practice the invention is particularly applicable to narrow film-strips, as these conform more readily to the helical path around the rollers. Thefilm passes first upward to and over'the roller 1, thence descends 'directly to the roller 3 and under the latter,

and is then led up again to the roller 1 and so on continuously. In the drawings most of the turns of film are omitted for simplicity in illustration. The filmis caused to travel through the apparatus by rotating the upper roller 1. To this end this roller is mounted upon a ower shaft 5 journaled in shaft-hangers 6 epending from'the ceiling. and is provided with a pulley 7 or equivalent means whereby-the apparatus may be driven from any suitable source of power.

The film 4 passes downward to a guideroller 8, and thence horizontally into the printing chamber or compartment of the apparatus. Beneath the guide-roller 8 is a pressing-roller 9. The negative film 10 is in the form of an endless strip. so that it is employed over and over indefinitely in printing successive portions of the film-strip 4. The negative passes under and around the pressing-roller 9 and into engagement with the film-strip 4, and the two strips thereafter travel in contact with each other through the printing chamber or compartment.

In order that the registration of the two films may not be disturbed while the printing operation is taking place. relative motion of the films must be absolutely prethis end a roller 11 engages the lower surface of the negative 10 immediately beneath the pressing-roller 9, and the roller 11 dips into a supply of adhesive contained in u receptacle 12, which is thus applied to the negative. As the same cement may be used over and over it is unnecessary to apply fresh cement constantly to the negative. and accordingly the roller 11 is shown as provided with a lever 11 for throwing it into or out of engagement with the negative. The cemented films enter the printing chamber, horizontally, and pass around and upwardly from a guide-roller 13 to the upper drive-roller 1. They then follow a helical course around the roller 1 and the lower roller 3, from one end to the other of the printing chamber. vIn the construction shown, the rollers are provided with peripheral flanges 1 and 3 respectively which guide the film.

The light by which the printing is performed may be produced by any convenient source such, for example, as mercury-vapor lamps 14. These lamps are arranged in a bank within the path of movement of the films, and the films, in passing from the guide-roller 13 to the roller 1, are given a quarter turn by which the negative is brought tothe inner position. so that the light from the lamps passes first through the negative and thusto the sensitized surface of the strip 4.

, The front of the printing compartment may be provided with a door 15 to afford access to the interior. To shield the film against the heat of the lamps, transparent sheets16 are interposed between the lamps and the film, and these sheets may be ruled gratings, heat-absorbing cells, or anv wellknown or suitable devices for absorbing. radiant heat. For the same purpose cool air is introduced-through an opening 17 in the door, the heated air being withdrawn from the too of the compartment through a conduit 18.

The printing apparatus just described is particularly adapted for use in connection with the bichromate process as it permits the fi m to be euposed for a long period to the action of the light. Obviously where more rapid senstitive material is employed such a long exposure is unnecessary. As the length of the negative varies according to the number of views, it is necessary to provide for adjustment of the length of the path through which the negative is extended. For this purpose-{the guide-roller 13 is mounted on a lug 19 which is adiustably supported by a horizontal beam 20 extending from end to end of the printing compartment. By adiu ting this guideroller along the beam the film may he arranged to make anv required number of turns about the rollersl and 3 less than the full number, and thus the length of negative in contact with the sensitized film is regulated. The exposure is correspondingly regulated by regulating the sources of illumination.

After the completion of the printing operation the film 4 is separated from the negative. As shown in Fig. 1, the strip 4. passes to the right around and under a guide-roller 21, while the negative passes to the left under a guide-roller 22 and returns to the pressing-roller 9, the two films being thus drawn apart. Means may be provided for removing from the surfaces of the filmstrip any cement which may remain thereon, and to this end I have illustrated a roller or rotary brush 23 which dips into a supply of suitable solvent, such as gasolene, in a reservoir 24. This roller engages the surface of the film, and to rotate the roller at a speed different from the surface speed of the film the roller is connected, by a belt 25, with a pulley 26 on the end of the roller 1. After the film leaves the printing chamber it may be treated to the usual developing, fixing, washing and drying operations.

The apparatus just described is adaptable, by modifications'which will be obvious to those skilled in the art, to the performance of any of the ordinary printing operations by which a strip ofprinted photographic film, or other material, may be produced, the helical path followed by the film being of utility in connection with all of such processes. The invention is not, therefore, limited to the details of construction and arrangement of the illustrated apparatus, but may be embodied in various other forms within the natureof the invention'as it is defined in the following claims.

The method of developing and the apparatus therefor are not claimed herein but form the subject-matter of a divisional application, Serial No. 766,595, filed May 9, 1913.

I claim- 1. The method of producing photographic prints which consists in immovably securing together, relatively to one another a strip of sensitized material and an endless strip of transparent printed film strip, and moving these strips in such condition past an actinic light to print the sensitized strip through the printed film strip, said printed film strip being continuously returned to the starting point for cotiperation with fresh portions of the sensitized strip.

2. The method of producing photographic prints which consists in cementing together a strip of sensitized material and an endless transparent printed film strip, moving said strips simultaneously and in printing relation past an actinic light, de-

taching said strips as they emerge from the influence of the light, and returning said moving said strips in such condition simu printed film strip continuously to the starting point for coiiperation with fresh por tions of the sensitized strip.

3. The method of producing photographic prints which consists in moving a strip of sensitized material and an endless transparent printed film strip simultaneously and continuously while in contact in a substantially helical course past an actinic light with the printed film strip arranged between the light and the sensitized material, and returning the film strip continuously to the starting point for cooperation with fresh portions of the sensitized material.

'4. The method of producing photographic prints which consists in cementing together a strip of sensitized material and an endless transparent printed film strip, taneously and continuously while in contact past an actinic light in a substantially helical course with the printed film strip arranged between the light and the sensitized material, separating said strips after they are subjected to the light, and returning the film strip continuously to the starting point for coiiperation with fresh portions of the sensitized material.

5. Apparatus for producing photographic prints comprising movable guiding means upon which a strip of sensitized material may be wound in a substantially helical path, means being provided for supplying said strip continuously at one end of said path, means being provided for removing sai st ip continu'c sly from the other e of sai pa h, and means f r feeding a med filmstrip to. tra el in printing re ati n ith said sensitized stri 6 Apparatus for p qdiicing photogra hic prints ha ing, in combination, two eongated guide rollers arranged with axes substantially parallel and separated by a sub-v stantial distance whereby a transparent printed film and a strip of sensitized material may be wound helically about said rollers with substantial portions of the lengths of said film and strip stretched in two planes between the rollers, means cooperative with the film to guide the said film and strip to and from said rollers, means being provided for supplying the sensitized strip continuously to and withdrawing it continuously from said rollers to cause said film and strip to travel together in a helical path about the rollers with the printed film in position for printing the sensitized strip, and a source of actinic light for subjecting the sensitized strip to printing action through the printed film while the printed film and sensitized strip are moving in contact with one another. a

7 Apparatus for producing photographic prints having, in combination, means for guiding and moving an endless transparent ing' said film and strip after cooperating with said guiding means, and a source of w actinic light to subject the film and the strip to a printing operation while traveling in said path JOHN EDWARD THORNTON.

Witnesses:

FARNUM F. Doesny', D. GURNEE. 

